Many types of playing card shufflers are known. One type of known shuffler includes a rotatable wheel having slots, where the wheel is rotated by a stepper motor. One or more decks of cards are placed into an input tray, and rollers forward cards into selected slots in the wheel. A microprocessor controls the stepper motor to align a selected slot with the card path. After the cards are loaded into the wheel, the microprocessor then controls the stepper motor to align randomly selected slots of the wheel with an output mechanism that discharges the cards from the slots into an output tray. The cards in the output tray may be dealt to the players as the cards are output from the wheel, or the dealer may wait until the entire contents of the wheel are discharged and then place the shuffled cards into a shoe for dealing to the players.
Another common shuffler randomly removes cards from a vertical stack of cards and places the removed cards in a separate stack. The stacks are then repeatedly combined and separated until the cards are shuffled. Another form of shuffler uses a vertical rack of compartments and places the cards into randomly selected compartments.
Additional shufflers are known. Examples of shufflers are described in U.S. patent application Ser. Nos. 10/009,411; 10/256,639; and 10/256,880, all by Ernst Blaha and Peter Krenn; and U.S. Pat. Nos. 6,267,248; 6,149,154; 5,695,189; 6,139,014; 6,068,258; 6,325,373; 6,019,368; and 4,586,712. These U.S. applications and patents are incorporated herein by reference.
In these various automatic shufflers, shuffling may not be truly random since the order of cards placed in the shuffler may have some effect on the final order of the shuffled cards. What is needed is a technique for further randomizing the cards output by an automatic card shuffler.